<!DOCTYPE html>
<html lang="en">

<title>canvas filters: remove referenced filter element through document.open()</title>

<body onload="loaded()">

<canvas id="canvas" width="10" height="10"></canvas>

<svg height="0">
  <filter id="filter">
    <feFlood flood-color="red"/>
  </filter>
</svg>

<script>

function loaded() {
  var ctx = document.getElementById('canvas').getContext('2d');

  ctx.filter = 'url(#filter)';
  ctx.fillRect(0, 0, 10, 10); // do a draw first to work around bug 1287316

  document.open();

  // The document.open() call removed #filter from the document. So the filter
  // reference should now be invalid, and the rect should be drawn without a
  // filter applied, resulting in black.
  ctx.fillRect(0, 0, 10, 10);

  try {
    var data = ctx.getImageData(0, 0, 1, 1).data;
    if (data[0] == 0 && data[1] == 0 && data[2] == 0 && data[3] == 255) {
      // Successfully painted black.
      document.write('PASS');
    } else {
      // Painted something else, like red.
      document.write('FAIL');
    }
  } catch (e) {
    document.write('getImageData failed');
  }
  document.close();
}

</script>
